The Elements of Causal Perception

• Applicant: Dr. Sven Ohl
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 519602062

The instantaneous detection of cause and effect in sensory events is critical for an understanding of our environment and for behaving adaptively. Even displays with simple geometric shapes can elicit strikingly clear impressions of one object causally launching a second object into motion. A strong tradition in experimental psychology argues that such phenomenological causality is perceptual in nature, which has been further supported by retinotopic aftereffects following the visual adaptation of causality. Extending this perspective, the present project pursues the novel hypothesis that causality emerges from computations in elementary, direction-selective, causality detectors that are located in early visual processing. Moreover, we will test our prediction that the output from these elementary causality detectors underlies the perception of causal interactions in increasingly complex and natural situations. In three subprojects, comprising ten experimental studies that combine psychophysics and eye-tracking, we strive to meet three main objectives. First, we will critically evaluate the hypothesis that causality is computed in elementary causality detectors by further constraining the processing stage of causality detectors within the visual system. To this end, we will use established behavioral protocols to determine the interocular transfer of adaptation and we will constrain the involved processing stages by varying the event’s location in the visual field. Second, we will decompose the launching event into its individual elements to determine what critical features of a launch adapt the perception of causality. To this end, we will determine the role of the launch kinematics, luminance changes, feature-conjunctions, and the need for two moving stimuli in adapting the perception of causality. Third, we will assess how the output from local elementary causality detectors can be integrated to provide a causal impression in increasingly complex stimuli and environments. To this end, we will assess whether and how the adaptation of causality transfers between simple launching events and launches in increasingly complex stimuli. Thus, we will determine the transfer between simple launches, launches during complex motion stimuli, and launches in photorealistic environments. The proposed project aims to uncover the mechanisms underlying causal perception by introducing direction-selective causality detectors that serve as flexible building blocks located in early vision. By investigating the critical elements that serve as input to the detectors and determining how the output is integrated in increasingly complex causal interactions, we will provide a new framework for understanding the detection of cause and effect in our visual environment.

• DFG Programme: Research Grants